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排序方式: 共有319条查询结果,搜索用时 15 毫秒
1.
2.
Michal Mann Clemens M H Hosman Herman P Schaalma Nanne K de Vries 《Health education research》2004,19(4):357-372
Self-evaluation is crucial to mental and social well-being. It influences aspirations, personal goals and interaction with others. This paper stresses the importance of self-esteem as a protective factor and a non-specific risk factor in physical and mental health. Evidence is presented illustrating that self-esteem can lead to better health and social behavior, and that poor self-esteem is associated with a broad range of mental disorders and social problems, both internalizing problems (e.g. depression, suicidal tendencies, eating disorders and anxiety) and externalizing problems (e.g. violence and substance abuse). We discuss the dynamics of self-esteem in these relations. It is argued that an understanding of the development of self-esteem, its outcomes, and its active protection and promotion are critical to the improvement of both mental and physical health. The consequences for theory development, program development and health education research are addressed. Focusing on self-esteem is considered a core element of mental health promotion and a fruitful basis for a broad-spectrum approach. 相似文献
3.
Intestinal schistosomiasis japonica: CT-pathologic correlation 总被引:1,自引:0,他引:1
Lee RC; Chiang JH; Chou YH; Rubesin SE; Wu HP; Jeng WC; Hsu CC; Tiu CM; Chang T 《Radiology》1994,193(2):539
4.
5.
Gene conversion is a likely cause of mutation in PKD1 总被引:3,自引:0,他引:3
Watnick TJ; Gandolph MA; Weber H; Neumann HP; Germino GG 《Human molecular genetics》1998,7(8):1239-1243
Approximately 70% of the gene responsible for the most common form of
autosomal dominant polycystic kidney disease ( PKD1 ) is replicated in
several highly homologous copies located more proximally on chromosome 16.
We recently have described a novel technique for mutation detection in the
duplicated region of PKD1 that circumvents the difficulties posed by these
homologs. We have used this method to identify two patients with a nearly
identical cluster of base pair substitutions in exon 23. Since pseudogenes
are known to be reservoirs for mutation via gene conversion events for a
number of other diseases, we decided to test whether these sequence
differences in PKD1 could have arisen as a result of this mechanism. Using
changes in restriction digest patterns, we were able to show that these
sequence substitutions are also present in N23HA, a rodent-human somatic
cell hybrid that contains only the PKD1 homologs. Moreover, these changes
were also detected in total DNA from several affected and unaffected
individuals that did not harbor this mutation in their PKD1 gene copy. This
is the first example of gene conversion in PKD1 , and our findings
highlight the importance of using gene-specific reagents in defining PKD1
mutations.
相似文献
6.
Two types of phantoms were developed with which to evaluate the overall performance of digital subtraction angiography (DSA) systems. A dynamic phantom, called a "fish bone" phantom, consists of polyethylene tubes that simulate blood vessels with various lesions, such as stenoses, ulcers, and aneurysms. With this phantom, washout curves were obtained representing the relationship between iodine content and time. It will be useful for qualitative assessment of DSA images, evaluation of different image-processing schemes, and studies of blood flow analysis. A static phantom, called a "C-D" phantom, can be used for measurement of quantitative contrast-detail (C-D) diagrams and for daily monitoring of DSA systems. This was constructed of tubes of seven different diameters (2.15-0.28 mm) and 14 different concentrations of contrast medium (100%-1.1% Renografin-76 [meglumine and sodium diatrizoate]). The C-D diagrams were determined from an observer performance study using C-D phantom images obtained at four different DSA settings. 相似文献
7.
This follow-up study was undertaken in an effort to ascertain the morbidity in the survivors of infants ≤2000 g birthweight cared for in the two Rockhampton intensive care nurseries.
The records of all infants ≤2000 g delivered in or transferred to Rockhampton during the 11 year period 1979 through 1989 inclusive were extracted. Efforts were made to contact and examine all of these children. Those found to be disabled were assessed as being mildly, moderately or severely affected.
Of the 482 infants of birthweight ≤2000 g treated in the period under review, 393 survived to be discharged from hospital. Eight were known to have died subsequently. Of the remaining 385 children, 288 (74.8%) were able to be contacted and their health status determined. A total of 36 infants were found to have significant disabilities. Twenty-four were mildly affected, five moderately and seven severely affected. Severe disability in infants of ≤1000 g was 16% (3/19).
The incidence of disability was established in 74.8% of the surviving population, It was not dissimilar to the incidence of disability in similar birthweight groups in some Australian tertiary centres for the years under study. It is emphasized that the follow-up was incomplete and recognized that the survival rates and incidence of disability in survivors has improved in tertiary centres since the time frame of this study. 相似文献
Methodology:
The records of all infants ≤2000 g delivered in or transferred to Rockhampton during the 11 year period 1979 through 1989 inclusive were extracted. Efforts were made to contact and examine all of these children. Those found to be disabled were assessed as being mildly, moderately or severely affected.
Results:
Of the 482 infants of birthweight ≤2000 g treated in the period under review, 393 survived to be discharged from hospital. Eight were known to have died subsequently. Of the remaining 385 children, 288 (74.8%) were able to be contacted and their health status determined. A total of 36 infants were found to have significant disabilities. Twenty-four were mildly affected, five moderately and seven severely affected. Severe disability in infants of ≤1000 g was 16% (3/19).
Conclusions:
The incidence of disability was established in 74.8% of the surviving population, It was not dissimilar to the incidence of disability in similar birthweight groups in some Australian tertiary centres for the years under study. It is emphasized that the follow-up was incomplete and recognized that the survival rates and incidence of disability in survivors has improved in tertiary centres since the time frame of this study. 相似文献
8.
Arif JM; Gairola CG; Glauert HP; Kelloff GJ; Lubet RA; Gupta RC 《Carcinogenesis》1998,19(8):1515-1517
The present study investigated the effects of dietary oltipraz on cigarette
smoke-related lipophilic DNA adduct formation. Female Sprague- Dawley rats
were exposed daily to sidestream cigarette smoke in a whole- body exposure
chamber 6 h/day for 4 consecutive weeks. One group of rats was maintained
on control diet while another group received the same diet supplemented
with either a low (167 p.p.m.) or high (500 p.p.m.) dose of oltipraz,
starting 1 week prior to initiation of smoke exposure until the end of the
experiment. Analysis of lipophilic DNA adducts by the nuclease P1-mediated
32P-post-labeling showed up to five smoke-related adducts. Adduct no. 5
predominated in both the lung and the heart while adduct nos 3 and 2
predominated in the trachea and bladder, respectively. Quantitative
analysis revealed that the total adduct level was the highest in lungs
(270+/-68 adducts/10(10) nucleotides), followed by trachea (196+/-48
adducts/10(10) nucleotides), heart (141+/-22 adducts/10(10) nucleotides)
and bladder (85+/-16 adducts/10(10) nucleotides). High dose oltipraz
treatment reduced the adduct levels in lungs and bladder by >60%, while
the reduction in lungs in the low-dose group was approximately 35%. In
trachea, the effect of low and high dietary oltipraz on smoke DNA adduction
was equivocal, while smoke-related DNA adducts in the heart were minimally
inhibited by high-dose oltipraz. In a repeat experiment that employed a
3-fold lower dose of cigarette smoke, oltipraz (500 p.p.m.) was found to
inhibit the formation of DNA adducts in rat lungs and trachea by 80 and
65%, respectively. These data clearly demonstrate a high efficacy of
oltipraz in inhibiting the formation of cigarette smoke-induced DNA adducts
in the target tissues.
相似文献
9.
Familial protein S deficiency with a variant protein S molecule in plasma and platelets 总被引:3,自引:0,他引:3
A protein S deficient family presenting a variant protein S molecule in plasma and platelets is described. The propositus, age 20, and two brothers suffered from venous thrombotic disease. The propositus, the only family member studied while taking oral anticoagulants, had a protein S antigen (ag) level of 17% and undetectable activity. As demonstrated by immunoblotting both the propositus and one clinically affected brother (42% ag, 7% activity) presented variant protein S molecules of 65,000 molecular weight (mol wt) while the other clinically affected brother (64% ag, 11% activity) had only protein S with normal electrophoretic mobility of 70,000 mol wt. The mother had normal protein S levels (93% ag, 100% activity) but had both normal and variant protein S molecules and based on her functional protein S data a normal anticoagulant activity of the variant molecule is suggested. One asymptomatic but protein S deficient sister (68% ag, 9% activity) as well as the asymptomatic protein S deficient father (59% ag, 10% activity) had only protein S molecules of 70,000 mol wt. The variant protein S bound to C4b-binding protein in plasma, and differed from normal protein S in carbohydrate content. Platelets of each family member contained the same immunoblotting pattern of normal and variant protein S forms as found in plasma, consistent with the hypothesis that protein S gene expression involves codominant expression of two alleles that is similar in cells that control the synthesis of both platelet and plasma forms of protein S. 相似文献
10.
Takeuchi S; Bartram CR; Miller CW; Reiter A; Seriu T; Zimmerann M; Schrappe M; Mori N; Slater J; Miyoshi I; Koeffler HP 《Blood》1996,87(8):3368-3374
Cytogenetic analysis of acute lymphoblastic leukemia (ALL) of childhood identified nonrandom chromosomal abnormalities of the short arm of chromosome 12. The alterations include deletions that are thought to be indicative of the presence of a tumor suppressor gene that is mutated on the remaining allele. To refine further the chromosomal localization of this gene, we analyzed the loss of heterozygosity (LOH) of chromosome 12 in 100 primary ALL samples using 22 polymorphic markers and identified two distinct smallest common deleted regions on chromosome 12p13. One region is flanked by D12S77 and D12S98 and has a size of 4 cM. Twenty-six percent of informative patients showed LOH in this region. This region may contain the TEL gene. The other region is flanked by D12S269 and D12S308 including the KIP1 gene. Forty-four percent of informative patients showed LOH in this second region. Mutational analysis of KIP1 using polymerase chain reaction-single- strand conformation polymorphism analysis and Southern blot analysis showed no homozygous deletions and point mutations suggesting that the altered gene in this second region is not the KIP1. Clinical data showed that LOH of 12p was demonstrated more frequently in precursor-B ALLs (32 of 80; 40%) than in T-ALLs (1 of 20; 5%) (P = .0027). Furthermore, patients with 12p LOH were younger (P = .013), with a lower DNA index (P = .046), but they had the same survival rates at 3 years. In summary, these data suggest that two different tumor suppressor genes are on chromosome arm 12p, which act separately in the development of childhood precursor-B ALLs. One of the tumor suppressor genes is in the region the KIP1 gene, but our data suggest this gene is not abnormal. The other target is in the region of the TEL gene; and this candidate deserves further study. 相似文献